javascript get find 方法

$get Shortcut Method

Provides a shortcut to the getElementById method of the Sys.UI.DomElement class. This member is static and can be invoked without creating an instance of the class.

Syntax

$get(id, element);   Term	Definition
id	The ID of the DOM element to find.
element	The parent element to search. The default is the document element.

Example

The following example shows how to use the $get method. This code is part of a larger example found in the DomElement class overview.

cs

// Add handler using the getElementById method 
$addHandler(Sys.UI.DomElement.getElementById("Button1"), "click", toggleCssClassMethod);
// Add handler using the shortcut to the getElementById method 
$addHandler($get("Button2"), "click", removeCssClassMethod);
vb

// Add handler using the getElementById method
$addHandler(Sys.UI.DomElement.getElementById("Button1"), "click", toggleCssClassMethod);
// Add handler using the shortcut to the getElementById method
$addHandler($get("Button2"), "click", removeCssClassMethod);
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$find Shortcut Method
Provides a shortcut to the findComponent method of the Sys.Application class. This member is static and can be invoked without creating an instance of the class.
Syntax
 
var o = $find(id, parent);
Arguments
id :
A string that contains the ID of the component to find.
parent :
(Optional) The component or element that contains the component to find.
Return Value
A Component object that contains the component with the specified ID, if found; otherwise, null.
Remarks
For details about the method that this shortcut represents, see findComponent Method.
Example
The following example uses the $find method to check whether a custom component exists and to notify the user if the component is missing.
CS
function checkComponent() {
    if (!($find('MyComponent', div1))) {
        div1.innerHTML = 'MyComponent is not available.';
    }
}